Clamping devices which are removably attached to a power tool housing are known. One such clamping device is shown in U.S. Pat. No. 3,834,019 to Smeltzer et al. The Smeltzer et al. patent describes an attachment having a tube engaging structure pivotally mounted to the tool housing. The tube engaging structure is movable between a tube receiving position and a cutting cycle completion position. In operation, a user engages the handle and moves the tube engaging structure into the tube receiving position. After a tube is inserted into the tube engaging structure, the user releases the handle. A spring, connected to the tube engaging structure, biases the tube engaging structure towards the cutting blade so that the tube is "clamped" between the tube engaging structure and the cutting blade. After the tube has been cut, it is no longer "clamped" and the two portions of the tube fall to either the side of the attachment.
Another clamping device for use with a hand-held tool is shown in U.S. Pat. No. 4,437,237 to Ducret (the '273 patent), who is also the named inventor of the present invention. The '237 patent discloses a removable clamping device comprising a work holding assembly having pivotally mounted side plates, best shown in FIG. 11 of the '273 patent. The plates extend downwardly and forwardly and carry an adjustable lower jaw. A nut/bolt combination is provided for manually moving the lower jaw to the appropriate location along the plates so as to clamp a work piece therein.
More specifically, the movable member of clamping jaw of the '237 patent is underneath the work piece; thus, the movable jaw member receives much of the force exerted on the work piece by the cutting blade and the user. Therefore, if the jaw member is not securely locked, it could slip from its position. In addition, the clamping member of the '237 patent must be manually tightened and loosened each time the operator desires to cut a work piece or release a work piece that has been cut. Further, the adjustable clamping member of the '237 patent is positioned under the cutting blade.
What is desired, therefore, is a clamping device which has an immovable portion of the clamping device bearing most of the force of the work piece and the user during the cutting cycle, which has a quick release mechanism to reduce the amount of time needed by the operator to clamp a work piece and/or remove a cut work piece, which is easily removed from and attached to a power tool housing, which can be attached to the power tool housing with little retooling, and which securely clamps work pieces of a variety of diameters.